Pulsed electric field and mild heating for milk processing: a review on recent advances.

BACKGROUND Pulsed electric field (PEF) treatment consist in exposing food to electrical fields between electrodes within a treatment chamber, which can improve the preservation of fresh-like products such as milk. Although several studies support the use of PEF technology to process milk at low temperature, these studies reported microbial reductions around to 3 log10 cycles and also indicated a limited impact of PEF on some endogenous and microbial enzymes. This scenario indicates that increasing impact of PEF on both enzymes and microorganisms remains as major challenge for this technology in milk processing. More recently, combining PEF with mild heating (below pasteurization condition) has been explored as alternative processing technology to enhance the safety and preserve the quality of fresh milk and milk products. RESULTS Mild heating with PEF enhanced the safety of milk and milk products (3-6 log10 cycles reduction on microbial load and drastically impact on the activity enzymes related to quality decay) in milk and derived products. Moreover, minimal impact on enzymes of technological and safety relevance, proteins, milk fat globules, nutrients (particularly for vitamins), and improved the shelf-life of milk and selected derived products were obtained from this approach. Finally, further experiments should consider the use of milk processed by PEF with mild heating on cheese-making. CONCLUSION The combined approach of PEF with mild heating to process milk and derived products is very promising. The characteristics of current PEF systems (which is being used at industrial level on several countries) and their use on liquid food industry, particularly for milk and some milk products, could advance towards this strategy. This article is protected by copyright. All rights reserved.